A motorcyclist was seriously injured this afternoon when involved in a crash along Route 309 in Lehigh County. The crash occurred around 2:30 p.m. as he was traveling south on the Blue Mountain. He apparently came in contact with another vehicle, causing him to lose control and lay the bike down. He was treated at the scene by Cetronia paramedics and transported to a nearby trauma center. Route 309 was closed to all traffic. State police at Fogelsville are investigating the incident.